package demo2;

import java.io.IOException;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.SocketException;

/**
 * Created with IntelliJ IDEA.
 * Description:
 * User: 石方旭
 * Date: 2022-08-14
 * Time: 11:17
 */
public class UdpServer {

    DatagramSocket socket = null;
    public UdpServer(int port) throws SocketException {
        socket = new DatagramSocket(port);
    }
    public String process(String request){
         return request;
    }

    public void start() throws IOException {
        System.out.println("服务器开始启动");
        while(true){
            DatagramPacket requestPacket = new DatagramPacket(new byte[4096],4096);
            socket.receive(requestPacket);
            String request = new String(requestPacket.getData(),0, requestPacket.getLength());
            String response = process(request);
            DatagramPacket responsePacket = new DatagramPacket(response.getBytes(),
                    response.getBytes().length,requestPacket.getSocketAddress());
            socket.send(requestPacket);
            System.out.printf("[%s : %d] req = %s;rep = %s\n",requestPacket.getAddress().toString(),
                    requestPacket.getPort(),request,response);
        }
    }

    public static void main(String[] args) throws IOException {
        UdpServer udpServer = new UdpServer(8000);
        udpServer.start();
    }
}
